Stuttery wiper

[Ruan]

Yeah as I remember it's the contacts inside the motor - the motor essentially sends it's park position back to the relay in intermittent mode so after a single wipe it pauses, it normally stutters like mad when the contact inside the motor which sends the position back is getting manky - usually when the grease inside has become conductive from the wiping of the contacts.

Try the relay first, but I have a funny feeling it's the contacts in the motor, if you're feeling brave, strip the motor down and you should see crap on the contacts which returns the park position.